#!/usr/bin/python3
# -*- coding: UTF-8 -*-

# my previous attempts at measuring outdoor light levels have kinda sucked
# this is attempt #2 using the veml7700 breakout board as provided by adafruit
# thanks adafruit!
#
# more here:
# https://www.adafruit.com/product/4162
# https://learn.adafruit.com/adafruit-veml7700?view=all
# https://circuitpython.readthedocs.io/projects/veml7700/en/latest/api.html

import time, sys, busio, board, adafruit_veml7700

sys.path.append('/home/ghz/wxlib')
import wxlib as wx

wx_dir = "/home/ghz/light_wx"
dat_fname='v2_light.dat'

i2c = busio.I2C(board.SCL, board.SDA)
vis = adafruit_veml7700.VEML7700(i2c)

# given our experience with the v1 light sensor, just set the
# gain and integration time to be as numb as possible. accuratley
# measuring light levels under one or two lux doesn't help us
# when it all looks like 0 on a graph that goes between 0-30klux.
#
# ALS_25MS, ALS_50MS, ALS_100MS, ALS_200MS, ALS_400MS, ALS_800MS
vis.light_integration_time = vis.ALS_25MS

# ALS_GAIN_2, ALS_GAIN_1, ALS_GAIN_1_4, ALS_GAIN_1_8
vis.light_gain = vis.ALS_GAIN_1_8

if __name__ == "__main__":

	vis_counts_total = 0
	vis_lux_total = 0
	count = 0

	while True:
		# viscount! haha!
		vis_counts = vis.light
		vis_lux = vis.lux

		if isinstance(vis_lux, float) and isinstance(vis_counts, int):
			vis_lux_total += vis_lux
			vis_counts_total += vis_counts
			count += 1

		if count >= 160:
			ts = time.strftime("%Y%m%d%H%M%S", time.gmtime())
			dat = "%s\tvis_lux: %.2f\tvis_counts: %d\tpi_temp_C: %.2f\n" % \
				(ts, vis_lux_total / count, vis_counts_total / count, float(wx.pi_temp_read()) / 1000)

			wx.write_out_dat_stamp(ts, dat_fname, dat, wx_dir)
			vis_counts_total = 0
			vis_lux_total = 0
			count = 0

		time.sleep(0.1)